There is evidence, by no means negligible, to support this. During Alexander's early lifetime, an educated Greek recorded that at the moment of conception Olympias's womb had been sealed with the mark of a lion, proving that her son would be lion-like; others said that her womb had been struck by a thunderbolt, emblem of Zeus, and these uncertainties may have been known to Alexander himself. In a letter, which may, however, be a forgery, he is said to have told Olympias that he would reveal the 'secret prophecies' of the Siwah oracle to her as soon as he returned to Macedonia; she died before he returned, but because this promise was made to his mother, it suggests that he had asked a question about his parentage and that this had already been discussed privately between the two of them. Morover, Olympias seems to have held views on the topic herself.

'Alexander's fame', wrote Callisthenes, very probably, 'depends on me and my history, not on the lies which Olympias spread about his parentage.' The lies, then, were a fact, and on setting out for Asia Alexander is said to have been 'told the secret of his birth' by his mother and 'ordered to act worthily of it', a doubtful story had it not been upheld by one of the finest scholars of the generation after Alexander's death, a man, moreover, who was known to be sceptical of all reports of Alexander's divinity: evidently, he was prepared to believe that Olympias had had views of her own on Alexander's parentage, however mistaken he thought them. To these private rumours, the nuances of an Athenian joke may again be relevant. At Alexander's accession, the orator Demosthenes had dismissed him as a mere Margites, but Margites was not only known as a Homeric buffoon: he was a sexual simpleton, who knew neither the facts of life nor the identity of his mother and father. The joke went down in history, perhaps because it was doubly appropriate: while it ridiculed Alexander as the new Achilles, it may also have mocked at a current rumour that his father had not been Philip, but some god in disguise, perhaps even Zeus himself. Alexander, a mere Margites, did not know who his parents were; Demosthenes had visited Pella in Alexander's youth, so there could be no better Greek witness to the gossip of Alexander's early years.

This is perhaps too ingenious to be decisive, but there are links with Sicilian Dionysius which suggest the background may be correct. Dionysius's father had had two sons by his two wives, one a Sicilian from his native Syracuse, the other a south Italian foreigner, and it was generally believed that the two sons had been conceived on one and the same night and the wives married on one and the same day. Now it was Dionysius, son of the foreigner, who succeeded his father, although he was the younger of the two; his rights to the succession were not beyond dispute, and a sincere claim to have been fathered by a god would help to give him the necessary pre-eminence. Perhaps this is why he described himself publicly as 'sprung from the intercourse of Phoebus Apollo'; he was also a poet of more pretension than ability and Apollo in particular may have appealed to him as the god of artists. Twenty years later, Olympias's circumstances had been noticeably similar. Though mother of a promising son, she had been dismissed from court in favour of a noble Macedonian wife and she had seen her son's succession threatened. Like Dionysius's mother, she was a foreigner; she was also a queen of heroic ancestry in her own right. Disappointed in her marriage or keen to assert her superiority over Philip's many other women, she might well have spread a story that her son was special because he owed nothing to Philip and was child of the Greek god Zeus. Sexual knowledge in the ancient world was not enough to refute her, for the role of the female in conception was unknown, as it remained until the nineteenth century, and if mares in Thessaly could be believed to conceive through the agencies of a brisk west wind there was no reason why the queen of Macedonia could not have been visited by Zeus in equivalent disguise. The kings and heroes of myth and of Homer's epic were agreed to be children of Zeus: Alexander, like many, may have come to believe of himself what he had begun by reading of others.

The belief was a Homeric one, entirely in keeping with the rivalry of Achilles which was Alexander's mainspring; if it had been latent when he entered Egypt, the traditions of the Pharaoh's divine sonship and the proceedings at Siwah's oracle could have combined to confirm it and cause its publication through Callisthenes to the Greek world. Perhaps by a fortunate slip of the tongue, perhaps by a private remark inside the oracular shrine as well as by his greeting on the steps, Ammon's priest had confirmed what Alexander may have long suspected from his mother, and the apparent chance of Ammon's confirmation need not discredit Alexander's own sincerity. His favour for Ammon was lasting, as was his new sonship; when his Macedonians mutinied at the end of their marching, they were said to have ridiculed him and told him to 'go and fight alone with his father', meaning Zeus, not Philip. The abuse of mutineers is seldom reported accurately, and as no witness described the mutiny, alternative versions of their insults survived. But the sonship of Zeus Ammon is known, independently, to have remained a topic at court, and discontented men have a way of picking on the insult which they know will be most wounding; Alexander, it seems, had taken his divine father to heart, and his soldiers knew it. But it was because of events at Siwah, not the Pharaoh's titles, that the sonship had first been confirmed.

This favour for Zeus might be thought to have lowered his respect for Philip, the more so if Alexander had been aware of the plans for his father's murder; psychologists, too, would willingly see Alexander's love for Hephaistion as a search for a father-figure, later found in Zeus. 'You pass yourself on to Amnion,' one of Alexander's officers is made to say, drunk and outraged, in a biography four hundred years later, 'and you have denied the claims of Philip', and yet there is no proof that this alleged complaint was ever justified. Four centuries later, a letter could be quoted, written as if from Alexander to the Athenians on the most vexed subject of Athenian politics of the day, in which Alexander is said to have referred to Philip as his 'so-called father'. Among so much fictitious correspondence in Alexander's name this letter cannot be taken as reliable, especially on so emotive a topic, and there are very strong grounds for dismissing it as later Athenian propaganda. It is more revealing that after Alexander's death, his successors promptly persuaded the army that one of his last plans had been to build a gigantic pyramid in Macedonia in Philip's honour. These plans had perhaps been faked by his officers to ensure their rejection, but they still had to seem plausible to the troops; the plan for the pyramid is proof that the two sick* ro Alexander's view of his father were widely credited by many ordinary men at the end of his life. He could be believed to honour Philip lavishly, for there was no proof that he had disowned him. But he could also be believed to wish to honour him in an Egyptian way, with a pyramid 'as large as that of Cheops the Pharaoh'; in Egypt, men thus were aware, Alexander the Pharaoh had found a truer father who might influence even the honours due to Philip. The plan for the pyramid proves what the troops believed of Alexander, not what Alexander believed of himself. But he was soon to move far beyond Philip's achievements, and the farther he moved, the more the special protection of Zeus Ammon must have appealed to him.

Legend, meanwhile, gathered rapidly round it, until Ammon was said to have visited Olympias in order to father her son; some said he came disguised as the last Pharaoh of Egypt, others as her pet snake, and even these absurdities became a theme of importance for the future. At Rome, for example, a hundred years later, Scipio the conqueror of Carthage was said by contemporaries to have been conceived by a snake because his glory was thought to rival Alexander's, while similar rumours were put about for Aristomenes, a hero of southern Greek freedom against Sparta, and for the future Emperor Augustus after his adoption by Julius Caesar, himself a momentary rival of Alexander. Not for the last time Alexander's royal myth lasted for more than three centuries as a spur and a pattern to ambitious men, but the myth itself looked back to the Homeric world.